Upper driveshaft bearing lubrication for marine propulsion unit

ABSTRACT

An arrangement for lubricating the upper bearing for a drive shaft in a marine propulsion unit. A disc-shaped member, which may be a gear used to drive a propeller, is situated below the upper bearing in the bore of a gearcase. Lubrication oil is supplied to the gearcase. There is a small clearance between the bore of the gearcase and the outside diameter of the disc-shaped member to prevent rapid leakage of oil from around the periphery of the disc-shaped member. The disc-shaped member when rotating acts as a centrifugal impeller throwing oil out from its center and up a passageway to the upper bearing. The lubricating oil spills over the upper bearing and returns to the gearcase by way of a drive shaft passage to provide a continuous lubricating means.

United States Patent 1131 3,647,024

Wick et al. 1 Mar. 7, 1972 1541 UPPER DRIVESHAFT BEARING 1,915,3306/1933 LUBRICATION FOR MARINE 1 936 111 11/1933 PROPULSION UNIT234401338 4/1948 2,458,813 1/1949 [72] Inventors: Gerald H. Wick,Menomonee Falls; 6, 1950 Theodore J. lloltermann, Milwaukee, both ofWis. Primary ExaminerManuel A. Antonakas Attorney-Robert K. Gerling,Robert E. Clemency, John W. [73] ASSgnee: outboard Mame C(lrpomuon,Michael, Gerrit D. Foster, Bayard'l'l. Michael, Paul R. Puerkegan nir,Joseph A. Gemignoni and Andrew 0. Riteris [22] Filed: Apr. 30, 1970 [21]App1.No.: 33,832

1 [57] ABSTRACT An arrangement for lubricating the upper bearing for adrive shaft in a marine propulsion unit. A disc-shaped member,

[52] US. Cl. ..184/6.l8,184/6.12, 123/196 W, which may be a gear used todrive a propeller, is situated 308/ 1 34.] below the upper bearing inthe bore of a gearcase. Lubrication [51] lnt.Cl ..F16n 7/16 oil issupplied to the gearcase. There is a small clearance [58] Field ofSearch ..184/6.18, 6.28, 6.12; between h r f th gearc e n the utsidediameter of 123 19 w; 303 134 415 10, 11 2 2 the disc-shaped member toprevent rapid leakage of oil from around the periphery of thedisc-shaped member. The disc- [56] References Cited shaped member whenrotating acts as a centrifugal impeller throwIng oIl out from Its centerand up a passageway to the UNITED STATES PATENTS upper bearing. Thelubricating oil spills over the upper bearing and returns to thegearcase by way of a drive shaft passage to 18.13115?!" ..184/6.l8provide a continuous lubricating means. 1 l 1,062,876 5/1913 Blymyer..415/ 122 6 Claims, 2 Drawing Figures ,l /|6 i I lz e is :i 1 f 56 t l2IO 1 I 1 lfl'l'ili 32 PATENTEDMAR 7 I972 INVENTORS THEODORE J.HOLTERMANN GERALD H.'WlCK UPPER DRIVESI-IAF'I BEARING LUBRICATION FORMARINE PROPULSION UNIT BACKGROUND OF INVENTION The invention relatesgenerally to marine propulsion devices, such as outboard motors andstern drive units,'and more particularly to lower units therefor. Thelower unit of a marine propulsion device is normally at least .partiallyin water and is conventionally vertically tiltable and horizontallyswingable to afford steering. Such marine propulsion devices or unitscommonly include a substantially upright drive shaft which is supportedby upper and lower bearings mounted in a drive shaft housing. The driveshaft drives a propeller shaft through a gearing arrangement normallymounted in a gearcase which is connected to the bottom of the driveshafthousing. More particularly, the invention relates to supplyinglubrication to the upper bearing located in spaced relation above thebottom of the drive shaft housing.

SUMMARY OF INVENTION The invention relates to an arrangement forlubricating an upper drive shaft bearing in a marine propulsion unit.

, A primary object of the invention is an improved means fortransferring lubricating oil to an upper gearcase bearing in a marinepropulsion unit.

A further object is a novel apparatus that acts as a centrifu- THEDRAWINGS The invention is illustrated by the accompanying drawingswherein:

FIG. 1 is a partial section view of the lower unit of a marinepropulsion unit; and

FIG. 2 is an enlarged view of a disc-shaped member inaccordance with theinvention.

DETAILED DESCRIPTION Referring to the drawings in more detail, it willbe seen that FIG. 1 shows a lower unit of a marine propulsion unit. Themarine propulsion unit may be either-an outboard motor or a stern driveengine which is supported for vertical tilting and horizontal swingingas is well known in the art. The lower unit 10 includes a drive shafthousing 12 connected to, or integral with, a gearcase 14.

The drive shaft housing 12 includes a drive shaft 16 operably connectedto a suitable source ofpower, such as the engine or motor. The driveshaft 16 ismounted'in an interior cavity 18 of the housing 12 and turnsin an upper bearing 20 and a lower bearing 22. A cap'24, which may bepart of the lower half of a water pump, retains the upper bearing 20inposition. In addition, it should be noted that the upper bearing 20 isshown as ball bearings while the lower bearing 22 is shown as'needlebearings, however, any type of bearings'may be used as long as theyprovide adequate support and allow the necessary rotating movement ofthe drive shaft 16.

The interior cavity 18 of the drive shaft housing preferablycommunicates with a bore 26' in the gearcase I4. The bore 26 holds asufficient quantity of lubricating oil 28 which may be supplied throughan aperture with a plug, not shown. The aperture may be located in thedrive shaft housing 12 for easy access.

As shown in FIG. 1, the drive shaft 16 engages a propeller shaft 30through a gearing arrangement to drive a propeller LII 32. The gearingarrangement includes a pinion 34 mounted on the lower end of the driveshaft 16 engaging a forward bevel gear 36 and a reverse bevel gear 38,both mounted on the propeller shaft 30. The propeller shaft may bemounted for rotation in bushings 40 and 41 at the forward end, and in abearing 42 atthe aft end of the gearcase. Another bearing-44 supportsthe gear 38for rotation on the propeller shaft. The gears 34, 36 and 38are always in mesh with eachother and the lubricating oil 28 iscontinuously circulatedto the upper bearing 20 except at extremely lowspeeds when the pressure developed is too low to raise the oil therequired distance.

The shaft mechanism is.not shown but maybe any conventional type such asan electrically actuated hydraulic power shift using gearcase oil toapply the forcerequired for shifting action, or an electric poweredshift using an electromagnetic coil. As shown in'FIG. l, the forwardbevel gear 36 and the reverse bevelgear 38 rotateindependently of thepropeller shaft 30 unless a clutch dog 46 is engaged by the shiftmechanism.

In accordance with the invention, FIG. 1 shows the reverse bevel gear 38having at least one axial transfer opening 48. The openings '48 may bedrilled through the gear and areprovided to permit movement of thelubricatingoil 28 between the forward and rearward portions of thegearcase 14.

At least one radial feed hole 50 leads from a center open portion 52 ofthe gear 38 to a groove 54 in the periphery of the gear. Two radial feedholes each having a diameter of approximately three thirty-seconds of aninch have been found to adequately supply lubricating oil to theperiphery of the gear. The rotating gear 38 acts as a centrifugalimpeller throwing lubricating oil out from the center of the gear up theradial feed hole 50 to the groove 54.

The groove 54 isformed by a pair of outer circumferencial edges or rims56 which have a small clearance with the bore 26 of the gearcase 14. Ithas been foundthat a clearance ranging from 0.0015 to 0.0035 inch workswell for the invention. This small clearance between the edges 56 andthe bore 26 limits the leakage of lubricating oil from the groove 54.The lubricating oil in the groove 54 is thus pressurized and made totravel up an oil passageway 58'formed in the drive shaft housing 12.

The oil passageway 58 may be approximately the same diameter as theradial feed holes 50. The oil passageway 58 leads to the upper bearing20 thus allowing the lubricating oil 28 to spill over the bearing andreturn to the gearcase 14 by way of the interior cavity 18in the driveshaft housing. In taking this path the returning oil also lubricates thelower bearing 22.

FIG. 2 shows the bevel gear 38 and various features of this inventioninmore'detail. The plurality of radial feed holes 50 supply thelubricating oil 28 to the periphery of the gear 38. The oil rotates inthe peripheralgroove'54 and-builds-up pressure as the rotational speedof the gear'increases. When the peripheral speed reaches approximately250 feet per minute or greater, sufficient pressure is built up to-pushthe oil'up the passageway 58 leading to the upper bearing 20. It hasbeen found that a passageway approximately 5 inches long works well withthe dimensions and speeds given herein. In addition it has been foundthat'the lubricating'an'angemcnt works well when thelubricating oil 28in the gearcase l4 fills-the bore 26 to a level which'reaches to thetop-of the center open portion 52, as shown in FIG. I.

In use the pinion 34 of thedrive shaft engages and rotates the bevelgears 36 and 38. The lubricating oil 28 is forced up the passageway 58to the upper bearing 20 by centrifugal force. The oil 'spills over theupper bearing 20 and returns to the gearcase 14 through the interiorcavity 18 of the drive shaft housing. Thus, a continuous supply oflubricating oil is provided for the upper bearing 20.

The axial transfer openings 48, radial feed holes 50, peripheral groove54 and other features have been shown and described'as located inthe-reverse bevel gear 38. It is important to note that these featuresmay be located in either or both bevel gears 36 and 38, or instead, maybe incorporated in a separate disc-shaped member. in addition, it shouldbe pointed out that the groove 54 may be formed or cast in the driveshaft housing 12 instead of being formed by the rims 56 in the gear 38.

Various features of the invention are set forth in the following claims.

What is claimed is:

1. A marine propulsion unit comprising a drive shaft housing, a driveshaft rotatably mounted in said housing, an upper bearing in saidhousing and supporting said drive shaft, a gearcase connected with saiddrive shaft housing below said bearing and adapted to contain a quantityof lubricating oil, a propeller shaft rotatably mounted in said gearcaseand driven by said drive shaft, an oil passageway independent of saiddrive shaft and extending from said gearcase to said upper bearing, anda disc-shaped member rotatably mounted in said gearcase for movementthrough the oil contained therein and driven by said drive shaft, saiddisc-shaped member including a feedline extending radially in saiddisc-shaped member and terminating, at its radially outer end, inposition for periodic communication with said oil passageway in responseto rotation of said disc-shaped member and adapted, at its radiallyinner end, for communication with the oil in said gearcase.

2. A marine propulsion unit as set forth in claim 1 wherein said driveshaft housing has an interior cavity formed around said drive shaft andcommunicating with said gearcase to allow the lubricating oil to becontinuously circulated by spilling over said upper bearing andreturning to said gearcase through said interior cavity.

3. A marine propulsion unit as set forth in claim 1 wherein saiddisc-shaped member has at least one axial transfer opening permittingmovement of lubricating oil through said diseshaped member.

4. A marine propulsion unit as set forth in claim 1 wherein saiddisc-shaped member includes a periphery having therein means defining aperipheral groove communicating with said feedline and with said oilpassageway.

5. A marine propulsion unit as set forth in claim 1 wherein saidgearcase includes a bore communicating with said oil passageway, andwherein said periphery of said disc-shaped member includes a pair ofaxially spaced circumferential edges having a small clearance with saidgearcase bore, and wherein said feedline terminates between said edges.

6. A marine propulsion unit as set forth in claim 1 including a piniongear on the lower end of said drive shaft and wherein said disc-shapedmember is a part of a bevel gear driven by said pinion gear.

1. A marine propulsion unit comprising a drive shaft housing, a driveshaft rotatably mounted in said housing, an upper bearing in saidhousing and supporting said drive shaft, a gearcase connected with saiddrive shaft housing below said bearing and adapted to contain a quantityof lubricating oil, a propeller shaft rotatably mounted in said gearcaseand driven by said drive shaft, an oil passageway independent of saiddrive shaft and extending from said gearcase to said upper bearing, anda discshaped member rotatably mounted in said gearcase for movementthrough the oil contained therein and driven by said drive shaft, saiddisc-shaped member including a feedline extending radially in saiddisc-shaped member and terminating, at its radially outer end, inposition for periodic communication with said oil passageway in responseto rotation of said disc-shaped member and adapted, at its radiallyinner end, for communication with the oil in said gearcase.
 2. A marinepropulsion unit as set forth in claim 1 wherein said drive shaft housinghas an interior cavity formed around said drive shaft and communicatingwith said gearcase to allow the lubricating oil to be continuouslycirculated by spilling over said upper bearing and returning to saidgearcase through said interior cavity.
 3. A marine propulsion unit asset forth in claim 1 wherein said disc-shaped member has at least oneaxial transfer opening permitting movement of lubricating oil throughsaid disc-shaped member.
 4. A marine propulsion unit as set forth inclaim 1 wherein said disc-shaped member includes a periphery havingtherein means defining a peripheral groove communicating with saidfeedline and with said oil passageway.
 5. A marine propulsion unit asset forth in claim 1 wherein said gearcase includes a bore communicatingwith said oil passageway, and wherein said periphery of said disc-shapedmember includes a pair of axially spaced circumferential edges having asmall clearance with said gearcase bore, and wherein said feedlineterminates between said edges.
 6. A marine propulsion unit as set forthin claim 1 including a pinion gear on the lower end of said drive shaftand wherein said disc-shapeD member is a part of a bevel gear driven bysaid pinion gear.